A comma separated list of fields to obfuscate in the full evaluation response (only relevant within the completed_evaluation type events, and provided the query parameter fullData is also set to true).
For example, if hideFields=document_ssn, then "document_ssn": "123456789" would be returned as "document_ssn": "*********".
This obfuscation will apply to the supplied, formatted, and meta objects in the full evaluation response, including inside nested objects within those objects.